GARI: THE FOOD OF THE PEOPLE

We have new innovative equipment for gari processing. We believe that these equipment will reduce the drudgery and the inevitable stress in the traditional grari processing method which has driven most of the village women out of gari processing and drastically increased the price of gari.

Gari is a major Nigerian staple food processed from cassava tubers. It comes in granular form but once mixed in hot water, turns into smooth solid paste. It is mostly carbohydrate and contains less than 2 percent protein. It is the commonest food among Nigerians. Gari can be eaten in different forms but the most common is with assorted soup and meat. It is not chewed like rice or yam but simply swallowed once dipped in the soup. It can be soaked in water and enhanced with sugar and milk and taken as a beverage.

The average dose of gari per person per meal is about 300g. We consume about 7.7 million tons of gari per year and this comes to about 30.7 millions tons of cassava at a ratio of 4 tons of cassava to one ton of gari. Nigeria currently produces about 41 million tons of cassava per year and about 75 percent of this goes into gari and other forms of processed food.

Gari production has been going down considerably over the years because most of the village women who process it manually are abandoning it because of its drudgery and tedious nature. They will rather sell their cassava tubers than seat by the fire all day only to produce few kilos of gari. This situation has resulted in the steady rise in the price of gari.

The last administration sensitized Nigerians into planting more cassava nd farmers responded positively and we are now the highest producers in the world. There is too much cassava and few processors. The Local Government Councils that are located in the Cassava producing areas can increase their internally generated revenues by establishing this simple, economical and mechanized gari processing plant in their areas. Also, Entrepreneurs, Community Development Groups, Cooperatives, Town Unions and village Groups can use it to empower their people and alleviate their poverty. It will create jobs and new opportunities for rural people where cassava is mostly grown.

The new Mechanical processing Equipment

They comprise of: the Hammer Mill, the Fermentation Rack, the Hydraulic Dewatering Press, the Granulator and the gari Roasting or Frying Pot which is a new innovation in gari processing.

PROCESSING OF GARI

Peeling

Gari processing starts with the peeling of the cassava where most of the cyanide resides. The skin of the cassava is made up of the outer thin papery layer and the leathery tough inner layer.

Peeling can be done mechanically or manually. Mechanical peelers peel as much as 2,400-2,500kg per hour with a wastage rate of 30-40 percent while manual peeling accomplishes 22kg per man/hour and wastage of 20-25 percent. Mechanical peelers are problematic because of the non uniform nature of the cassava roots and the irregularity in size which make smooth peeling difficulty. Also, the thickness of the skin, the texture and the strength of adhesion to the flesh of the tuber differ from specie to specie thereby making over-peeling and under-peeling possible. As a result of these problems, processors prefer manual peeling for now till the mechanical is perfected.

Grating

After the manual peeling, the tubers are sliced and then taken to the washing tanks where they are thoroughly washed to remove all traces of sand. It is recommended that the tubers be washed before and after peeling to ensure the elimination of all traces of sand.

The washed tubers are taken by trolley to the Hammer Mill where they are grated. Proper grating disintegrates the root cells of the cassava tubers and releases the enzyme to act on its substrate thus initiating the process of fermentation and detoxification.

The Hammer Mill is made of stainless steel and equipped with 15 hp electric motor and has a capacity of 1 ton/hr. It is rugged and resilient and can withstand protracted operation.

The grated mash is emptied into the porous polypropylene bags at the rate of 25 kg per bag, tied by hand and taken by the trolley to the fermentation racks.

Fermentation

The bags are stacked in racks and depressed with hydraulic weight for three to five days to enable the liquour to drain out while fermentation takes place. Food scientists and gari experts have found that the sack-pressed method is the fastest and the best of the fermentation methods. Continuous pressure on the mash hastens detoxification more than when it is simply left in its liquour such as in non draining situation. Continuous pressure also lowers the residual hydrocyanic acid content. Fermentation of cassava for gari is best at 350c and does not occur in water; the natural liquour in cassava provides the needed moisture.

The essence of fermenting the mash is to get rid of the hydrocyanic acid (HCN) which is natural in cassava tubers. The acid is poisonous if taken in an unusual dose and can cause goiter, nervous breakdown and other health complications.

The expected HCN content of cassava ranges from 16- 40 milligrams of HCN per 100gm and varies with varieties, environment and age. According to the Standard Organization of Nigeria (SON), the maximum HCN allowed in gari is 20 parts per million (PPM). During fermentation process, acetic and lactic acids are produced and natural drainage of fermented liquor caries with it much of the hydrocyanic acid. The pH of properly fermented cassava mash in gari production is between 4.0 and 4.2.

Fermentation is the heart of gari processing because it is where the poisonous acid (HCN) is detoxified and removed to make the gari edible.

Pressing

The fermented mash in bags are stacked in the Hydraulic Jack Press and pressed mechanically to squeeze out the remaining fermented liquour. After about ten minutes of pressing, the bags are repacked and pressed for another thirty minutes and then removed and taken to the Granulator to be broken up into smaller pieces.

Granulating

Granulating is breaking up the dewatered mash into small lumps to facilitate roasting or frying. The Granulator is made of stainless steel and powered with a 7.5 hp motor; the capacity is 1 ton/hr.

The granulating mash is emptied into trolley and taken to the gari Roasting Pot. If the lumps are still big after granulating, they can be further milled in the hammer mill before roasting.

Roasting or Frying

The mash is emptied into the roasting pot which is a round roasting equipment of about 5ft in diameter with rotating flexible paddles or rakes for tuning the roasting mash to prevent sticking and charring. It is made of stainless steel with 2hp gear motor. It stands at about 3.5ft high and is fired with charcoal, firewood, gas etc. It is well ventilated with exhaust pipes and insulated with fiberglass.

The mash is first roasted or fried at about 150oC for about 40 minutes and then for another 20 minutes at a reduced temperature to allow air to blow over it so as to reduce the moisture content to about 9-10 percent.

After frying, the gari can be further milled in the Hammer Mill to further reduce the particular size so as to vary the product profiles. Small, medium and large particle sizes can be produced to meet the needs of different segments of the market.

The Roasting Pot is a new innovation in gari making because it reduces the drudgery, the burden and the stress in gari frying. Gari can now be fried with less stress, more output and in a shorter time.

Packaging

The Gari is discharged from the duct in the gari Roaster and packaged in 5,10 and 25kg bags stitched and stored in the storage area from where they are evacuated to the customers.

Qualities of the Gari Produced with the Equipment

It will have a moisture content of 9-10 percent. This means that microbial contamination and infestations will not easily affect it.

The shelf life will be over 6 months. Government authorities can easily procure it as part of our food security against disasters and emergencies.

Sand content is less than 1 percent making it and excellent product to compete with those from other places. Our gari has always been classed low because of high sand content

Cyanide content is less than 10 percent which is the acceptable SON and NAFDAC standards.

There are different particle sizes to meet the tastes of different customers.